What is a discount calculator?
A discount calculator shows how much an item costs after a percentage reduction. Enter the original price and the advertised percentage off to see the amount saved and the discounted price. You can also add a sales tax percentage to estimate the final amount after tax. It is useful for comparing promotions, checking a sale label or planning a purchase.
The tool works entirely in your browser. Nothing you enter is uploaded or stored. You can use any currency because it performs percentage calculations only: enter a price in dollars, pounds, rupees or another currency and the result stays in that same unit.
How to calculate a discount
- Enter the regular or original price of the product or service.
- Enter the discount percentage shown by the retailer, such as 20 for 20% off.
- Add sales tax if you know it; leave it at zero when it does not apply or is already included.
- Read the savings, discounted price, tax amount and estimated final price.
For example, a 20% discount on 100 saves 20 and leaves a discounted price of 80. If a 5% sales tax applies after the discount, the tax is calculated from 80, making the estimated final price 84. The calculator applies the reduction first and then adds your entered tax rate.
How the formula works
The saving is the original price multiplied by the discount percentage divided by 100. Subtracting that saving from the original price gives the price after discount. If sales tax is included, the calculator multiplies the discounted price by the tax rate and adds that tax to find the estimated final price.
This order matters because many sellers calculate tax after a discount is applied, but rules vary. Some prices already include tax, some products have different tax treatments and some offers use fixed-amount coupons instead of a percentage discount. This calculator is designed for a single percentage discount with an optional percentage tax.
Why check the final price?
The largest percentage off is not always the lowest final cost, especially when comparing products with different original prices, tax rules, shipping costs or exclusions. Checking the amount saved and the final estimate helps make the promotion easier to understand. Treat the result as a quick planning figure: retailer calculations may differ because of shipping, eligibility requirements, bundled promotions, local tax rules and rounding. Confirm the amount at checkout before buying.